JP7295102B2 - Single crystal diamond embedded in polycrystalline diamond structure and method of growing same - Google Patents

Description

The present invention relates to single crystal diamond embedded in polycrystalline diamond and methods of growing same.

Diamond is known for its unique physical, optical and electrical properties. Advances in diamond growth techniques, such as chemical vapor deposition (CVD) and high pressure and high temperature (HPHT), have made it possible to obtain diamond with desirable, controllable and reproducible properties.

In general, diamond grown using the growth techniques described above can be single crystal diamond (ie, single crystal diamond) or polycrystalline diamond (ie, multigrain diamond). In most cases, single crystal diamond has significantly better properties than polycrystalline diamond. However, full adoption for single-crystal diamond in all envisioned applications is largely constrained by two problems: industrial scalability and process feasibility. Accordingly, in such cases, polycrystalline diamond and/or other alternative materials appear to dominate and continue to be preferred.

For example, consider material selection for bare/unprocessed wafers. The superior quality of single crystal diamond is believed to make it a consistently preferred material of choice for wafers on which electronic circuits can be formed. However, to date, the diamond-growing industry has not been able to produce large enough single crystal diamonds to replace other commonly used materials (eg, silicon) in a viable industrial option.

Another example is the processing feasibility of thin film single crystal diamond. The superior properties of thin film single crystal diamond are highly appreciated in radiation detectors, especially for radiotherapeutic treatments being developed to combat diseases such as cancer. Radiation detectors are utilized to deliver protons to selected areas (eg, target cells on the body). Such precision is made possible only by the excellent properties of single crystal diamond as a transmission channel for protons without attenuating or affecting proton trajectories. However, thin single crystal diamond is typically brittle and can easily cleave whenever it is being processed.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the above-mentioned problems faced by single crystal diamond.

A summary of certain embodiments disclosed herein follows. These aspects are presented merely to provide the reader with an overview of certain embodiments thereof, and are not intended to limit the scope of the present disclosure. must understand. Indeed, the present disclosure can encompass various aspects not listed below.

In one embodiment, a method of growing a buried single crystal diamond structure is provided. The method includes placing a single crystal diamond on a non-diamond substrate, the non-diamond substrate being larger than the single crystal diamond. The method further includes obscuring the top portion of the single crystal diamond using a masking material. Finally, the method includes growing polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond using chemical vapor deposition (CVD) growth methods.

In another embodiment, the methods shown in the above embodiments are capable of growing embedded single crystal diamond structures. Embedded single crystal diamond structures include single crystal diamond and polycrystalline diamond. The polycrystalline diamond surrounds the monocrystalline diamond and is arranged in such a manner that the monocrystalline diamond is suspended between the polycrystalline diamond.

Various refinements of the above-described features may exist in relation to various aspects of the present disclosure. Further features may be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For example, various features discussed below in connection with one or more of the exemplary embodiments may be incorporated singly or in any combination in any of the above-described aspects of the invention. Again, the summary presented above is merely intended to familiarize the reader with certain aspects and contexts of the disclosed embodiments of the present invention without limitation to the claimed subject matter.

Various aspects of the present disclosure can be better understood upon reading the following detailed description and upon reference to the drawings.

1 illustrates an exemplary embedded single crystal diamond structure according to one embodiment of the present invention; FIG. 1 illustrates an exemplary embedded single crystal diamond structure according to one embodiment of the present invention; FIG. 1A and 1B illustrate different exemplary formation stages of the embedded single crystal diamond structure of FIGS. 1A and 1B according to one embodiment of the present invention; FIG. 1A and 1B illustrate different exemplary formation stages of the embedded single crystal diamond structure of FIGS. 1A and 1B according to one embodiment of the present invention; FIG. 1A and 1B illustrate different exemplary formation stages of the embedded single crystal diamond structure of FIGS. 1A and 1B according to one embodiment of the present invention; FIG. FIG. 2 illustrates an exemplary single crystal diamond array within a polycrystalline frame according to one embodiment of the present invention; FIG. 3 illustrates a method of growing a buried single crystal diamond structure according to one embodiment of the present invention;

One or more specific embodiments are described below. In order to provide a concise description of these embodiments, not all features of actual implementations are described herein. It must be recognized that any such practical deployment will require a number of implementation specific decisions to be made in order to achieve specific goals of diamond growth, and that this may vary from implementation to implementation. Further, it should be recognized that such efforts may be complex and time consuming, but are nevertheless considered routine practice for those skilled in the art who benefit from the present disclosure.

As discussed in more detail below, embodiments of the present disclosure generally relate to single crystal diamond embedded in a polycrystalline diamond frame. Indeed, such embedded single crystal diamonds are useful in mechanical applications such as viewing windows in abrasive atmospheres, cutting and attrition applications, etalons, laser windows, light reflectors, diffractive optical elements, anvils, etc. electronic applications such as detectors, heat spreaders, high power switches in power plants, high frequency field effect transistors, and light emitting diodes; microwave applications such as window gyrotrons, microwave components, antennas , acoustic applications such as surface acoustic wave (SAW) filters, aesthetic applications such as gemstones, and many other applications.

Figures 1A and 1B, which are meant to be illustrative and not limiting, show embedded single crystal diamond structures. 1A and 1B are top and side views, respectively, of an embedded single crystal diamond structure 130. FIG.

Embedded single crystal diamond structure 130 includes single crystal diamond 110 and polycrystalline diamond material 120 . As shown in FIG. 1A, polycrystalline diamond material 120 completely surrounds the side edges of single crystal diamond 110 .

Embedded single crystal diamond structure 130 can be used in a variety of applications. Specifically, the embedded single crystal diamond structure 130 can be used in the optical, detector, semiconductor, and/or electronic fields according to the list provided above.

In addition, the embedded single crystal diamond structure 130 can also overcome the challenges described in the background in one embodiment. However, it should be recognized that not all variations of the claimed invention are capable of overcoming the problems described in the background without departing from the general inventive concept of the invention.

In one embodiment, embedded single crystal diamond structure 130 may not cleave even when single crystal diamond 110 is a thin film single crystal diamond having a thickness of less than 20 microns. Devices/machines (e.g., detectors in radiotherapy applications) are held over a thick portion of the embedded single crystal diamond structure 130 (i.e., polycrystalline diamond material 120), thus overcoming processing feasibility issues. be able to.

In one embodiment, single crystal diamond 110 may be natural diamond or grown diamond. Grown diamond can be grown using a chemical vapor deposition (CVD) growth process or a high pressure high temperature (HPHT) growth process. A CVD growth process is preferred for obtaining consistently pure diamond.

Furthermore, single crystal diamond 110 can also form a semiconductor. In one exemplary embodiment, single crystal diamond 110 is formed in a semiconductor by implanting certain types of dopants (eg, boron, etc.). It should be recognized that once doped, single crystal diamond 110 may also be referred to as doped single crystal diamond 110 (eg, boron doped single crystal diamond). Doping single crystal diamond 110 with a particular type of dopant can form a semiconductor material such as negative type (N-type), positive type (P-type), and/or N+P type. In addition, single crystal diamond 110 may be isotopically pure diamond or isotopically enriched diamond. In one embodiment, single crystal diamond 110 may be an isotopically enriched or pure diamond with either ^13C or ^12C .

Still referring to FIG. 1A, a single crystal diamond 110 can have its two orthogonal lengths with dimensions X1 and Y1. In one embodiment, the values of X1 and Y1 may be 1 millimeter (mm) and 1 mm, respectively. In such an embodiment, the area encompassed by the faces of single crystal diamond 110 is 1 mm ² . In another embodiment, the values of X1 and Y1 can be 2 mm and 2 mm, respectively. In such an embodiment, the area encompassed by the faces of single crystal diamond 110 is 4 mm ² . In general, the size of the area can be highly dependent on the application for which single crystal diamond 110 will be utilized. For example, radiation therapy applications would require a single crystal diamond 110 having a size of at least 1 mm ² . In another example, semiconductor applications may require single crystal diamond 110 having a size of at least 4 mm ² .

Referring now to FIG. 1B, the thickness of single crystal diamond 110 is represented by dimension Z1. Those skilled in the art will appreciate that the thickness of single crystal diamond 110 may vary depending on the application of embedded single crystal diamond structure 130 . In one exemplary embodiment, the value of Z1 may be 20 microns (μm). In radiotherapy applications such as those described above where thin film single crystal diamond is desired, the value of Z1 can be 2 μm or less. In another exemplary embodiment, in applications where thick single crystal diamond is preferred, the value of Z1 is in the order of millimeters (eg, greater than 0.2 mm).

Single crystal diamond 110 may be relatively pure diamond. In one embodiment, such pure single crystal diamond 110 has the properties listed below:
a) Single substituted nitrogen (Ns) < 1 parts per billion (ppb)
b) Thermal conductivity >1500 Watts per meter per Kelvin (Wm ^-1 K ^-1 ) at 300K
c) charge collection distance with full collection >0.1 volt per micron (V/μm) when measured using alpha and beta sources d) charge collection efficiency of 100% >0.1V /μm
e) a charge carrier lifetime for electrons at 300 K >21.4±5.5 nanoseconds (ns)
f) charge carrier lifetime for holes >25.65±1.3 ns at 300 K
g) a birefringence smaller than Δn<1×10 ⁻⁴ h) between 70% and 72% light transmission at 10.6 μm and/or i) 1 or more of a rocking curve width >7 μRad can have:

It should be recognized that the desired properties of single crystal diamond 110 depend on its application. For example, in semiconductor applications, it is preferable to have almost all of the above properties (ie, properties (a)-(i)). Alternatively, for optical applications, it preferably has at least some of the properties described above (eg, properties (g)-(h)).

Single crystal diamond 110 may be in the form of a plate. The plate can be a parallel-sided plate. In one embodiment, the plate can have six sides. In such embodiments, the top and bottom surfaces of single crystal diamond 110 are of crystal orientation (100) and the sides of single crystal diamond 110 are of crystal orientation (110). In another exemplary embodiment, the plate may have six faces, but all faces will have a (100) crystallographic orientation. In another exemplary embodiment, the plate may have six faces, but the top and bottom faces have a crystallographic orientation (111) and the sides have any other crystallographic orientation (111, 110, 100 etc.).

Still referring to FIGS. 1A and 1B, polycrystalline diamond material 120 surrounds the entire side edge of single crystal diamond 110 . The dimensions of polycrystalline diamond material 120 formed from the edge of single crystal diamond 110 can be represented by X2 and Y2. In one embodiment, the value of X2 may be greater than 0.5 mm. The values of X2 and Y2 may increase depending on the application. For example, applications that require larger polycrystalline facets to facilitate processing will have larger X2 and Y2 values. In embodiments in which the single crystal diamond 110 has only a very small area (e.g., X1 and Y1 dimensions of 10 μm and 10 μm or less, respectively), the values of X2 and Y2 are 0.5 mm and 0.5 mm or less, respectively. Note that we may still stay at something greater than . The purpose of maintaining the X2 and Y2 values is to provide sufficient ease of processing.

Notwithstanding the embodiments illustrated in FIGS. 1A and 1B, polycrystalline diamond material 120 may also be formed to surround only a selected portion of the perimeter of single crystal diamond 110 . In other words, polycrystalline diamond material 120 may not surround the entire side edge of single crystal diamond 110 . The purpose of the polycrystalline diamond material 120 surrounding the selected perimeter of the single crystal diamond 110 is to do the bare minimum while providing sufficient structural holding support and processing area.

FIG. 1B shows the thickness of the polycrystalline diamond material 120. FIG. As shown in FIG. 1B, the thickness of single crystal diamond 110 is, in one embodiment, similar to polycrystalline diamond material 120 (ie, Z1) except for the side closest to single crystal diamond 110 . Further details as to why the sides of polycrystalline diamond material 120 differ in thickness from bulk polycrystalline diamond material 120 are provided below through FIGS. 2A-2C. Nevertheless, in one embodiment, such uneven thickness along polycrystalline diamond material 120 can be avoided using additional polishing and/or etching steps.

It should be recognized that the thickness of the polycrystalline diamond material 120 can be fixed, while the thickness of the single crystal diamond 110 is application dependent. For example, the thicknesses of single crystal diamond 110 and polycrystalline diamond material 120 may be similar when single crystal diamond 110 has a thickness greater than 200 μm. However, in embodiments where the thickness of single crystal diamond 110 is relatively small (eg, for a thin single crystal diamond having a thickness of 2 μm), the thicknesses of polycrystalline diamond material 120 and single crystal diamond 110 will be different. In such embodiments, the thickness of polycrystalline diamond material 120 will remain greater than 200 μm. In such situations, the embedded single crystal diamond structure 130 may have non-uniform surfaces. In one embodiment, such uneven surfaces may resemble "valley-like" surfaces, whereby the thin film single crystal diamond 110 forms the base of the valley. In another embodiment, the single crystal diamond 110 can be suspended midway through the thickness of the polycrystalline diamond material 120 to form a structure similar to a "dumbbell" structure. The thickness of the polycrystalline diamond material 120 remains the same to allow easy processing of such thin single crystal diamond 110 .

In one embodiment, the purity level of polycrystalline diamond material 120 may be similar to single crystal diamond 110 . In embodiments where single crystal diamond 110 has the highest purity level of single crystal diamond (i.e., it has all of the properties (a)-(i) described above), the purity level of polycrystalline diamond material 120 is also the same as that of single crystal diamond 110. It should be close to the purity level. Similar purity levels of single crystal diamond 110 and polycrystalline diamond material 120 ensure that there is no mismatch in properties between the two dissimilar materials, which generally play a limited role in post-processing steps. It is a fruit. In one embodiment, the similarity of purity levels may allow mechanical polishing of the entire top or bottom surface of embedded single crystal diamond 130 . In alternative embodiments, similar purity levels may also allow further formation of other structures without significant property mismatch between single crystal diamond 110 and polycrystalline diamond material 120 .

In one embodiment, the properties of polycrystalline diamond material 120 may be similar to polycrystalline diamond used in optical applications. This characteristic can include a Fourier Transform Infrared Spectroscopy (FTIR) value at 10.6 μm of at least 70%.

The bond at the interface of single crystal diamond 110 and polycrystalline diamond material 120 is seamless and nearly invisible. Furthermore, the boundary between single crystal diamond 110 and polycrystalline diamond material 120 is also non-permeable. Raman FWHM was measured at room temperature using a 514 nanometer (nm) laser along a seamless, nearly invisible boundary. In one embodiment, the Raman FWHM for single crystal diamond 110 near the boundary is 2 cm ⁻¹ and for polycrystalline diamond material is 2.5 cm ⁻¹ . Each of these values indicates a well-defined seamless and nearly invisible transition between monocrystalline diamond 110 and polycrystalline diamond 120 . That is, such perfect transitions can enable the use of the embedded single crystal diamond structure 130 in any vacuum-equivalent application (eg, optical windows for detectors).

It should be recognized that polycrystalline diamond material may be described as a form of diamond material that is composed of randomly arranged crystals and contains large angle grain boundaries, twin boundaries, or both. In contrast, a single crystal diamond material is one in which the crystal lattice of diamond is continuous and uninterrupted to the edges of the sample with no grain boundaries.

In one embodiment, a method of growing a buried single crystal diamond structure is provided. The method includes placing a single crystal diamond on a non-diamond substrate, the non-diamond substrate being larger than the single crystal diamond. The method further includes obscuring the top portion of the single crystal diamond using a masking material. Finally, the method includes growing polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond using chemical vapor deposition (CVD) growth methods.

Figures 2A-2C, by way of illustration and not limitation, illustrate formation stages 200A, 200B, and 200C, respectively, when growing a buried single crystal diamond structure according to one embodiment of the present invention. The buried single crystal diamond structure in FIGS. 2A-2C may, in one embodiment, be similar to the buried single crystal diamond structure 130 of FIGS. 1A and 1B.

FIG. 2A, by way of example and not limitation, shows the initial formation stage of an embedded single crystal diamond structure according to one embodiment of the present invention. The initial formation stage 200A includes a stacked structure made from a non-diamond substrate 220, a single crystal diamond 230, a frame structure 240, and a masking material 250. As shown in FIG. This structure is further placed on the substrate holder 210 of the CVD growth chamber.

A single crystal diamond 230 is placed over a non-diamond substrate 220, as shown in FIG. 2A. In one embodiment, non-diamond substrate 220 may be silicon, silicon carbide (SiC), tungsten, and/or any other suitable material. A non-diamond substrate 220 is used as a base for the growth of polycrystalline diamond. In one embodiment, the single crystal diamond 230 position relative to the non-diamond substrate 220 is believed to address processing issues and/or array formation issues. FIG. 2A shows that the single crystal diamond 230 is substantially centered on the non-diamond substrate 220 . A central arrangement can allow for the growth of polycrystalline diamond material surrounding the single crystal diamond 230 . Alternatively, single crystal diamond 230 is placed on the edge of non-diamond substrate 220 . Such an arrangement would allow growth of polycrystalline diamond material on one or more edges of single crystal diamond 230, as described above in FIGS. 1A and 1B.

Single crystal diamond 230 can be in the form of a plate. The plates can be parallel-sided plates. Each of these plates can have six faces. In one embodiment, the top and bottom surfaces of single crystal diamond 230 are of (100) crystal orientation and the sides of single crystal diamond 230 have a (110) crystal orientation.

Still referring to FIG. 2A, frame structure 240 surrounds the side edges of single crystal diamond 230 . Frame structure 240 may be utilized to prevent any polycrystalline growth on single crystal diamond 230 .

In another embodiment, the frame structure 240 may surround only a portion of the area of single crystal diamond to refrain from any polycrystalline diamond growth. In such an embodiment, the single crystal diamond outside the frame structure 240 will grow diamond, while the single crystal diamond 230 within the frame structure 240 will not grow. The frame structure 240 can be constructed from diamond material or silicon material. Although the frame structure 240 may resemble a wall structure, it should be appreciated that in Figures 2A-2B the frame structure 240 appears to be two stand-alone stanchions.

Disposed over framework 240 is masking material 250 . As shown in FIG. 2A, masking material 250 completely covers the top surface of single crystal diamond 230 . Masking material 250, as the name suggests, is used to isolate areas on single crystal diamond 230 from any growth. Masking material 250 inhibits growth by disabling gas or plasma from reaching the face of single crystal diamond 230 . That is, there is no growth in areas surrounded by framework 240 and blocked by the masking material. In one embodiment, masking material 250 may be composed of silicon carbide.

As described above, the structures in the initial formation stage 200A are placed above the substrate holder 210. FIG. Substrate holder 210 is a substrate typically used for CVD growth processes. In one embodiment, the substrate holder 210 is molybdenum (Mo) and does not contain any intentional placement of diamond seeds or diamond nucleation sites to enable growth of polycrystalline diamond material.

By way of illustration and not limitation, FIG. 2B shows a post-growth formation stage 200B immediately after growth conditions according to one embodiment of the present invention. In one embodiment, the only difference between the initial formation stage 200 A of FIG. 2A and the post-growth formation stage 200 B of FIG. 2B is the layer of polycrystalline diamond 260 . Polycrystalline diamond 260 is grown using a polycrystalline diamond growth process. It can be clearly seen from FIG. 2 that the polycrystalline diamond 260 is disposed immediately above the plasma exposed areas of the non-diamond substrate 220, the single crystal diamond 230, the frame structure 230 and the masking material 250. FIG. In one embodiment, the growing step can be a long enough step to grow polycrystalline diamond 260 having a thickness of at least 1-2 mm.

In one embodiment, the step of growing polycrystalline diamond using a CVD method can include supplying a gas having at least 0.5% to 10% methane (CH4) in hydrogen to the CVD growth chamber. The growth conditions will be in the range of at least 750 degrees Celsius to 1250 degrees Celsius. Pressure conditions range from 100 kilopascals (KPA) to 300 KPa.

FIG. 2C, by way of example and not limitation, shows the final formation stage of forming the embedded single crystal diamond structure. In one embodiment, the final formation stage 200C may resemble the embedded single crystal diamond structure 130 of FIGS. 1A and 1B. The final forming stage 200C can be accomplished by removing the non-diamond substrate from the bottom of the single crystal diamond 230 and by removing the frame structure 240 and masking material 250. FIG. It should be appreciated that the non-diamond substrate, framework 240 and masking material 250 can be easily removed as they are simply detached after growth of the polycrystalline diamond material 260 .

As shown in FIG. 2C, the thickness of the side of polycrystalline diamond material 260 that is closer to single crystal diamond 230 is different than the thickness of the rest of polycrystalline diamond material 260 . The non-uniform thickness of polycrystalline diamond material 260 results from the manner in which frame structure 230 is placed for the CVD growth process. Post-growth formation stage 200B shows the growth of polycrystalline diamond material following the contours of frame structure 230 within the edge of single crystal diamond 230 . That is, upon removal of frame structure 240 and masking material 250, the side of polycrystalline diamond material 260 near single crystal diamond 230 is relatively thick.

Nevertheless, the non-uniform thickness of the polycrystalline diamond material 260 is, in one embodiment, made uniform by a method of polishing (i.e., mechanical polishing) when the embedded single-crystal diamond material is relatively thick. can be done. Alternatively, the uneven thickness of polycrystalline diamond material 260 can be made uniform by etching (ie, reactive ion etching (RIE)) when single crystal diamond 230 is relatively thin. In one embodiment, the homogenization step only to the extent that it removes the non-uniform thickness of polycrystalline diamond material 260 without directly or indirectly affecting the remaining areas of polycrystalline diamond material 260 and single crystal diamond 230. is performed, the surface roughness of the top surface of the polycrystalline diamond material 260 within the now uniformed portion may be different than the remaining area of the polycrystalline diamond material 260 .

FIG. 3, by way of example and not limitation, shows a single crystal diamond array within a polycrystalline diamond frame according to one embodiment of the present invention. Single crystal diamond array 300 includes six single crystal diamonds 320A-320F secured to polycrystalline frame 310. As shown in FIG. In one embodiment, single crystal diamond array 300 can include at least more than one single crystal diamond. The quality of single crystal diamonds 320A-320F may be similar in one embodiment. Alternatively, and depending on the application, the quality of the single crystal diamonds 320A-320F (eg, size, thickness, origin (eg, mined or grown), type (eg, Ia, Ib, IIa, or IIb), purity, colors, materials, dopants) may be different.

The method of forming the single crystal diamond array 300 is similar to the method of forming the embedded single crystal diamond 130 of FIGS. 1A and 1B, and the embedded single crystal diamond structure shown in FIGS. 2A-2C. The only difference is believed to be the tiling of the single crystal diamonds 320A-320F prior to polycrystalline 310 growth. In one embodiment, single crystal diamonds 320A-320F can be placed at precise locations on a non-diamond substrate and grown such that these single crystal diamonds to connect connect.

In one embodiment, embedded single crystal diamond structure 130 allows for the formation of arrays of single crystal diamond. It must be admitted that there are many uses for such an arrangement. In one embodiment, single crystal diamond arrays can be used as individual substrates that can be formed into electronic circuits that receive a single process stream rather than each individual substrate that receives a process stream individually. Additionally, arrays of single crystal diamond arrays also help create redundancy in the detector. That is, with such redundancy, if a single crystal diamond is somewhat damaged, another single crystal can be switched to replace the damaged single crystal diamond.

By way of illustration and not limitation, FIG. 4 is a flow diagram of a method for growing a buried single crystal diamond structure according to one embodiment of the present invention. The embedded single crystal diamond structure may be similar to embedded single crystal diamond structure 130 of FIGS. 1A and 1B, or embedded single crystal diamond structure shown by final formation stage 200C of FIG. 2C.

At step 410, single crystal diamond is placed on a non-diamond substrate. In one embodiment, the single crystal diamond and non-diamond substrates may be similar to single crystal diamond 230 and non-diamond substrate 220 of FIGS. 2A-2C.

At step 420, the top portion of the single crystal diamond is masked using a masking material. In one embodiment, the masking material may be similar to the frame structure 240 and masking material 250 of Figures 2A and 2B. Masking material may be applied to only selected areas of the single crystal diamond. The configuration after stage 420 may resemble the initial formation stage 200A as shown in FIG. 2A.

At step 430, polycrystalline diamond material is grown surrounding the single crystal diamond. Such growth of polycrystalline diamond material joins single crystal diamond to polycrystalline diamond. The growth step may use a CVD growth method as provided in the embodiment of FIG. 2B. Further, the results immediately after stage 430 may be similar to the post-growth formation stage 200B of FIG. 2B.

At step 440, the masking material and non-diamond substrate are etched away from the embedded single crystal diamond. In one exemplary embodiment, the immediate result of stage 440 may be similar to final forming stage 200C of FIG. 2C.

Optionally, at step 450, the embedded single crystal diamond within the embedded single crystal diamond may be etched to reduce its thickness. Etching can be performed using RIE in one embodiment. The thinning function is essential for the purpose of forming thin film diamond at thicknesses less than 20 μm and is feasible to process simultaneously. In one embodiment, the final structure after thinning may resemble a “valley” surface or dumbbell-like structure.

It will be apparent to those skilled in the art that many modifications, substitutions, and variations can be made to the preferred embodiments of the invention described above without departing from the spirit and scope of the invention. Accordingly, it is intended to embrace all such modifications, alterations and variations that fall within the scope of the included claims.

Any reference herein to prior art should not be taken as an admission in any way that this prior art forms part of the common general knowledge.

Many modifications may be made to the preferred embodiment of the invention described above without departing from the spirit and scope of the invention.

that the term "comprises" or grammatical variations thereof as used in the specification and claims is equivalent to the term "includes" and should not be taken as excluding the presence of other features or elements; will be understood.

In one embodiment, a method of growing an embedded single crystal diamond structure comprises placing a single crystal diamond on a non-diamond substrate larger than the single crystal diamond and using a masking material to hide a top portion of the single crystal diamond. and growing a polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond material using a chemical vapor deposition (CVD) growth chamber.

The above method further includes etching the masking material and the non-diamond substrate from the embedded single crystal diamond structure.

The above method further includes further reducing the thickness of the single crystal diamond embedded in the embedded diamond single crystal structure. The above method, wherein the non-diamond substrate is a silicon substrate.

In the above method, the step of hiding the top portion of the single crystal diamond includes placing a frame structure over the top portion of the single crystal diamond in contact with a surrounding area that can be protected from growth; locating a blocking structure to block growth of crystalline diamond material.

In the method described above, the polycrystalline diamond material being grown has a purity similar to that of single crystal diamond.

The above method further includes polishing the planar surface of the embedded single crystal diamond structure. In the above method, the thickness of the non-diamond substrate is greater than 1 millimeter (mm).

In the method described above, the single crystal diamond is one of a plurality of single crystal diamonds disposed on a non-diamond substrate, and the single crystal diamonds are bonded together through the polycrystalline diamond.

The above method, wherein the single crystal diamond is thin film single crystal diamond.

In another embodiment, the embedded single crystal diamond structure comprises
a. single crystal diamond, and b. a polycrystalline diamond surrounding at least one edge of the single crystal diamond, the single crystal diamond suspended between the thickness of the polycrystalline diamond.

The embedded single crystal diamond described above is a thin film single crystal diamond.

The embedded single crystal diamond described above is chemical vapor deposition (CVD) diamond.

In the embedded single crystal diamond structure described above, the single crystal diamond has a thickness of less than 10 microns (μm).

In the embedded single crystal diamond structure described above, the single crystal diamond has an area of 1.0 millimeters ² (mm ² ) by 1.0 mm or greater.

In the embedded single crystal diamond structure described above, the thickness of the polycrystalline diamond has a thickness greater than 3 mm.

In the embedded single crystal diamond structure described above, the single crystal diamond and the polycrystalline diamond have the same purity.

In the embedded single crystal diamond structure described above, the single crystal diamond is one of a plurality of single crystal diamonds, all of which are structurally held together using polycrystalline diamond.

In one embodiment, a method of growing a buried single crystal diamond structure is provided. The method includes placing a single crystal diamond on a non-diamond substrate, the non-diamond substrate being larger than the single crystal diamond. The method further includes obscuring the top portion of the single crystal diamond using a masking material. Finally, the method includes growing polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond using chemical vapor deposition (CVD) growth methods. The method forms embedded single crystal diamond structures including single crystal diamond and polycrystalline diamond. A polycrystalline diamond surrounds the monocrystalline diamond and the monocrystalline diamond is suspended between the polycrystalline diamonds.

In the embedded single crystal diamond structure described above, the single crystal diamond is one of a plurality of single crystal diamonds, all of which are structurally held together using polycrystalline diamond.

In some embodiments, a method of growing an embedded diamond structure is provided. The method includes placing at least one single crystal diamond on a non-diamond substrate, the non-diamond substrate being larger than the single crystal diamond. The method further includes obscuring the top portion of the single crystal diamond using a masking material. Finally, the method includes growing polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond using chemical vapor deposition (CVD) growth methods. The method forms embedded single crystal diamond structures including single crystal diamond and polycrystalline diamond. A polycrystalline diamond surrounds the monocrystalline diamond and the monocrystalline diamond is suspended between the polycrystalline diamonds.
The following embodiments of the invention are described.
(Embodiment 1) A method of growing an embedded single crystal diamond structure, comprising:
placing a single crystal diamond on a non-diamond substrate larger than the single crystal diamond;
obscuring a top portion of the single crystal diamond using a masking material;
using a chemical vapor deposition (CVD) growth chamber to grow the polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond material. how to.
Embodiment 2. The method of embodiment 1, further comprising etching the masking material and the non-diamond substrate from the embedded single crystal diamond structure.
Embodiment 3. The method of embodiment 1 or 2, further comprising further reducing the thickness of the single crystal diamond embedded in the embedded diamond single crystal structure.
(Aspect 4) A method according to any one of aspects 1 to 3, wherein the non-diamond substrate is a silicon substrate.
(Embodiment 5) The step of hiding the top surface portion of the single crystal diamond comprises:
placing a frame structure over the top portion of the single crystal diamond in contact with a surrounding area that can be protected from growth;
5. The method of any one of claims 1-4, further comprising placing a blocking structure on the frame structure to block the growth of polycrystalline diamond material.
Aspect 6. A method according to any one of aspects 1 to 5, wherein the polycrystalline diamond material grown has a purity similar to that of the single crystal diamond.
(Embodiment 7) polishing a planar surface of the embedded single crystal diamond structure;
7. The method of any one of claims 1-6, further comprising:
Aspect 8. A method according to any one of aspects 1 to 7, wherein the thickness of the non-diamond substrate is greater than 1 millimeter (mm).
(Embodiment 9) The single crystal diamond is one of a plurality of single crystal diamonds arranged on the non-diamond substrate,
9. The method of any one of claims 1-8, wherein the single crystal diamonds are bonded together through polycrystalline diamond.
(Embodiment 10) A method according to any one of embodiments 1 to 9, wherein the single crystal diamond is a thin film single crystal diamond.
(Embodiment 11) Single crystal diamond,
a polycrystalline diamond surrounding at least one edge of said single crystal diamond, said polycrystalline diamond being suspended between the thickness of said polycrystalline diamond. Single crystal diamond structure.
Embodiment 12. The embedded single crystal diamond structure of embodiment 11, wherein said embedded single crystal diamond structure is a thin film single crystal diamond.
Embodiment 13. The embedded single crystal diamond structure of embodiment 11, wherein said embedded single crystal diamond structure is chemical vapor deposition (CVD) diamond.
Embodiment 14. The embedded single crystal diamond structure of embodiment 11, wherein said single crystal diamond has a thickness of less than 10 microns ([mu]m).
(Embodiment 15) The embedded single crystal diamond of Embodiment 14, wherein said single crystal diamond has an area of 1.0 millimeters ² (mm ² ) x 1.0 mm or greater. structure.
Embodiment 16. An embedded single crystal diamond structure according to embodiment 15, wherein said thickness of polycrystalline diamond has a thickness greater than 3 mm.
Embodiment 17. The embedded single crystal diamond structure of embodiment 16, wherein said single crystal diamond and said polycrystalline diamond have the same purity.

Claims (16)

A method of growing an embedded single crystal diamond structure, comprising:
placing a single crystal diamond on a non-diamond substrate larger than the single crystal diamond;
obscuring a top portion of said single crystal diamond using a masking material, said step of obscuring said top portion of said single crystal diamond removing a frame structure in contact with a surrounding area that can be protected from growth; said top portion of said single crystal diamond, further comprising placing on said top portion of said single crystal diamond; and placing a blocking structure on said frame structure for blocking growth of polycrystalline diamond material. said step of hiding the
using a chemical vapor deposition (CVD) growth chamber to grow the polycrystalline diamond material surrounding the single crystal diamond to bond the single crystal diamond to the polycrystalline diamond material;
A method comprising: etching the masking material and the non-diamond substrate from the embedded single crystal diamond structure;
2. The method of claim 1, further comprising: further reducing the thickness of the single crystal diamond embedded in the embedded single crystal diamond structure;
3. The method of claim 1 or claim 2, further comprising: 4. The method of any one of claims 1-3, wherein the non-diamond substrate is a silicon substrate. 5. A method according to any preceding claim, wherein the polycrystalline diamond material grown has a purity similar to that of the single crystal diamond. polishing a planar surface of the embedded single crystal diamond structure;
6. The method of any one of claims 1-5 , further comprising: 7. The method of any one of claims 1-6 , wherein the thickness of the non-diamond substrate is greater than 1 millimeter (mm). the single crystal diamond is one of a plurality of single crystal diamonds disposed on the non-diamond substrate;
wherein said single crystal diamonds are bonded together through polycrystalline diamond;
A method according to any one of claims 1 to 7 , characterized in that: 9. A method according to any preceding claim, wherein the single crystal diamond has a thickness of less than or equal to 2 [mu]m . single crystal diamond,
A polycrystalline diamond surrounding at least one edge of the single crystal diamond, wherein the thickness of the polycrystalline diamond is greater than the thickness of the single crystal diamond, and the boundary between the single crystal diamond and the polycrystalline diamond is 2 cm −1 ^. the polycrystalline diamond having a Raman full width at half maximum (FWHM) of 2.5 cm ⁻¹ from
A buried single crystal diamond structure comprising: 11. The embedded single crystal diamond structure of claim 10 , wherein said single crystal diamond has a thickness of 2 [mu]m or less . 11. The embedded single crystal diamond structure of claim 10, wherein said single crystal diamond has a thickness of 20 [mu]m or less. 11. The embedded single crystal diamond structure of claim 10 , wherein said single crystal diamond has a thickness of less than 10 microns ([mu]m). 14. The embedded single crystal diamond structure of claim 13 , wherein said single crystal diamond has an area of 1.0 (mm) x 1.0 mm or greater. 15. The embedded single crystal diamond structure of claim 14 , wherein said thickness of polycrystalline diamond has a thickness greater than 3 mm. 16. The embedded single crystal diamond structure of claim 15 , wherein said single crystal diamond and said polycrystalline diamond have the same purity.

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